Dose Dividing Delivery Device

ABSTRACT

A simple method and device enabling a unit dose from a reservoir is provided. The dose is drawn into the reservoir and is then expelled from the device by depressing a plunger. The plunger has features which divide the dose into discrete intervals. As the plunger is moved during delivery, the features on the plunger and the features connected to a barrel interact to provide for intermittent stops to the delivery. Other aspects of the device provide for reduced dead space, safety and selective interconnection with other devices. Thus, the device divides the dose.

This application is continuation of U.S. patent application Ser. No.13/922,779 filed Jun. 20, 2013 which is a continuation of U.S. patentapplication Ser. No. 12/864,685 filed Feb. 1, 2011, now abandoned, whichis a National Stage Application under 35 U.S.C. §371 of PCT ApplicationNo. PCT/IB2008/001028, filed Jan. 30, 2008.

FIELD OF THE INVENTION

The present invention relates generally to delivery devices fordelivering substances such as drugs, vaccines and the like, and morespecifically relates to a drug delivery system and device having asystem for dividing the dose into multiple sub-doses for injectionthrough a needle. More specifically, the present invention relates to amethod and apparatus for filling, dosing and disposing an intradermaldelivery device using a needle sized for intradermal delivery and a dosedivider for dividing the dose for multiple injections using the sameneedle.

BACKGROUND OF THE INVENTION

Traditionally, syringes are filled by inserting the needle into a vial.The dose is drawn from the vial, pulling the liquid drug dose from thevial into the syringe. The dosage is then expelled from the device bydepressing the plunger. If it is desired to divide the total dose intodiscrete intervals, it must be accomplished manually, or via complicatedand costly systems. In the actual usage of devices of this type,multiple doses are given to the same patient at various locations. Witha conventional syringe the practitioner must stop depressing the plungerbased on visual feedback (from the scale on the syringe). Consequently,it is difficult to perform the repeat dose injections with a high degreeof accuracy and/or precision. Furthermore, intradermal injections whichcan be performed at repeated sites are difficult to perform and addingthe difficulty of manually dividing the dose at each site hashistorically been difficult. Medication pens were developed to producemultiple injections, but are complicated and comprised of many parts.For example, a pen like device is described in U.S. Pat. No. 4,592,745.This pen device is complicated and performs multiple injections but withsignificant cost. Furthermore, medication pens are not readily adaptedfor use with fill at time of use systems, especially systems whichrequire reconstitution steps. What is needed is a device and techniquefor expelling repeated doses from a fill able single syringe to performmultiple injections without having to solely rely on visual feedbackfrom the scale of the syringe, or complicated devices with multipleparts. Furthermore, what is needed is a system that divides the dosethat is compatible with conventional reconstitution practices. Attachedare the results of a general background search which was conducted forthe dose dividers.

SUMMARY OF THE INVENTION

In one embodiment the medication device having aspects of the inventionuses a radially moving collar having a cantilevered beam which serves asa pawl. The collar is slidable from a first position to a secondposition on the flange of the syringe barrel. Furthermore, the plungerof the device is ratcheted with a plurality of spaced detents. In thefirst position the collar is positioned such that the pawls of thecantilevered beams do not interact with the ratchets of the plunger. Afilling needle is attached to the syringe barrel. The first position isthe filling position and allows the syringe to be used as a conventionalsyringe; however, in the usage of this device, the first positionprimarily serves to fill the syringe using a filling needle withoutinterference by the ratchets. The filling needle is removed from thebarrel and an injection needle is attached. The collar is moved to asecond position. In the second position the collar is positioned suchthat the pawls of the cantilevered beams interfere with the detents ofthe plunger. This position allows the syringe to be used as a multiplerepeat dose device. The practitioner inserts the needle into the patientand depresses the plunger. As the plunger is depressed, the pawlsinteract with the detents which provide for tactile feedback to thepractitioner that the discrete intermediate dosage has been delivered.The practitioner then moves the needle to a new injection site andrepeats the process. This process continues until the entire dose isdelivered.

In another embodiment having aspects of the invention, the device uses aradially slidable component having a follower. The component is slidablefrom a first position to a second position on the flange of the syringebarrel or on an intermediate part snapped on the syringe flange.Furthermore, the sides of the plunger are grooved with a track having aplurality of spaced units having at least a stop portion. In someembodiments the track has an angled portion, and in others there is acapture portion. In alternate embodiments the track is along thecontoured radial surface of the plunger, as the track. In yet anotherembodiment, the track is configured with units such that the follower iscaught in retention areas. In alternate embodiments the plunger containsa plurality of followers and the track is on the slider, thus reversingthe location of the features on the parts. In the first position thecomponent is positioned such that the follower of the component does notinteract with the tracks of the plunger. Optionally, a filling needle isattached to the syringe barrel. The first position is the fillingposition and allows the syringe to be used as a conventional syringe;however, in usage of this device the first position primarily serves tofill the syringe using a filling needle (or injection needle) withoutinterference by the follower/tracks. The filling needle is removed fromthe barrel and an ID injection needle is attached. The component ismoved to a second position. In the second position the component ispositioned such that the follower of the component is riding in thetrack of the plunger, and is at the start of an injection cycle. In thiscase it is at the bottom of a unit. This is the discrete injectionposition and allows the syringe to be used as a multiple repeat dosedevice. The practitioner inserts the needle into the patient anddepresses the plunger. As the plunger is depressed and begins to movedistally, the follower travels along the track. As the follower travelsalong the angled portion of the track, the component is moved to a thirdposition which is intermediate to the first and second position. At thecusp of the unit, the follower hits a stop point, which is the beginningof the adjacent unit, wherein the plunger is prevented from movingdistally. The practitioner then moves the component from the thirdposition to the second position which places the follower at thebeginning of angled portion of the adjacent unit. The practitioner thenmoves the needle to a new injection site and repeats the process. Thisprocess continues until the entire dose is delivered.

BRIEF DESCRIPTION OF THE DRAWINGS

Other advantages of the present invention will be readily appreciated asthe same becomes better understood by reference to the followingdetailed description when considered in connection with the accompanyingdrawings wherein:

FIG. 1 shows a perspective view of a delivery device having aspects ofthe invention.

FIG. 2 shows and Enlargement of Detail “A” of the delivery device ofFIG. 1.

FIG. 3 shows a side view of the distal end of the device of FIG. 1 withthe shield of the device removed.

FIG. 4 shows a perspective view of a slider of the embodiment of FIG. 1.

FIG. 5 shows side view of a plunger of the embodiment of FIG. 1.

FIG. 6 shows a perspective view of a slider/clip assembly of the deviceof FIG. 1.

FIG. 7 shows a perspective view of a slider, clip and plunger assemblyof the device of FIG. 1.

FIG. 7A shows a perspective view of a clip and plunger assembly of analternate embodiment having aspects of the invention.

FIG. 8 shows an enlarged side view of the plunger of FIG. 5.

FIGS. 9A and 9B show an enlarged side view of Detail “B” and Detail “C”the plunger of FIG. 5, respectively.

FIG. 10 shows a cross-sectional view of the hub and barrel assembly ofFIG. 3 with the sheath and shield removed for clarity.

FIG. 11A shows a perspective view of an alternate embodiment of a clip,plunger and barrel having aspects of the invention.

FIG. 11B is a reverse perspective view of the components of FIG. 11A.

FIG. 12 shows an enlarged side view of a plunger used in the embodimentof FIGS. 11A-B.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

As used herein, the term “proximal” and derivatives thereof, shall meanthe end of an item or direction closest to the caregiver during use ofthe subject invention. The term “distal” and derivatives thereof, shallmean the end of an item or direction towards a patient during use of thesubject invention. As used herein, the term “drug substance” andderivatives thereof shall mean any substance that is intended forinjection into a patient, including, by way of non-limiting example,drugs, vaccines, therapeutics, and the like. It will be obvious to aperson of skill in the art, and from the disclosure provided herein,that the subject invention is not limited or otherwise defined by thetype or class of substance administered using the inventive injectiondevice.

For many drug substances, it may be desirable to fill the deliverydevice at the point of, and immediately prior to use. In this situation,the delivery device is normally filled from a unit dose or multi-dosevial. A multi-dose vial may be more economical and it enables the userto fill the delivery device with the specific dose required.Alternatively, the syringe is pre-filled with a diluent. Alternatively,the syringe is pre-filled with the drug substance, and no filling stepis required, and in this case the follower may be pre-set to be withinthe track. The multi-dose vial may be pre-filled with a liquid substanceor with a dry substance. For example, it is now conventional to reducecertain drugs to a dry or powdered form to increase the shelf life ofdrugs and reduce inventory space. Multi-dose vials are typically sealedwith an elastomeric stopper or septum. A needle on the delivery devicemay be used to pierce the stopper or septum and draw the drug substancefrom the vial into the delivery device, typically a syringe. The drugsubstance may then be administered using the delivery device, which isdiscarded after use, and the unit-dose vial may be stored for furtheruse. Alternatively, the drug substance may be contained in a cryogenicvial. Furthermore, the cryogenic vial may be involved in a complexmulti-step reconstitution procedure.

Standard methods for preserving the therapeutic and/or diagnosticsubstances, such as maintaining them in liquid or powder form inconventional vials for future use, may be used with the intradermaldevices of the present invention. The substances for use with the deviceand method include vaccines and certain medicaments and drugs.Additionally, these substances can be used for diagnostic testing suchas, for example, the Mantoux test to determine immunity status againsttuberculosis and immediate hypersensivity status of Type I allergicdiseases. Also, the substance preferably intradermally delivered inaccordance with aspects of the methods and devices of the presentinvention is selected from the group consisting of drugs, vaccines andthe like used in the prevention, diagnosis, alleviation, treatment, orcure of disease, with the drugs including Alpha-1 anti-trypsin,Anti-Angiogenesis agents, Antisense, butorphanol, Calcitonin andanalogs, Ceredase, COX-II inhibitors, dermatological agents,dihydroergotamine, Dopamine agonists and antagonists, Enkephalins andother opioid peptides, Epidermal growth factors, Erythropoietin andanalogs, Follicle stimulating hormone, G-CSF, Glucagon, GM-CSF,granisetron, Growth hormone and analogs (including growth hormonereleasing hormone), Growth hormone antagonists, Hirudin and Hirudinanalogs such as hirulog, IgE suppressors, Insulin, insulinotropin andanalogs, Insulin-like growth factors, Interferons, Interleukins,Leutenizing hormone, Leutenizing hormone releasing hormone and analogs,Low molecular weight heparin, M-CSF, metoclopramide, Midazolam,Monoclonal antibodies, Narcotic analgesics, nicotine, Non-steroidanti-inflammatory agents, Oligosaccharides, ondansetron, Parathyroidhormone and analogs, Parathyroid hormone antagonists, Prostaglandinantagonists, Prostaglandins, Recombinant soluble receptors, scopolamine,Serotonin agonists and antagonists, Sildenafil, Terbutaline,Thrombolytics, Tissue plasminogen activators, TNF-, and TNF-antagonist,the vaccines, with or without carriers/adjuvants, includingprophylactics and therapeutic antigens (including but not limited tosubunit protein, peptide and polysaccharide, polysaccharide conjugates,toxoids, genetic based vaccines, live attenuated, reassortant,inactivated, whole cells, viral and bacterial vectors) in connectionwith, addiction, arthritis, cholera, cocaine addiction, diphtheria,tetanus, HIB, Lyme disease, meningococcus, measles, mumps, rubella,varicella, yellow fever, Respiratory syncytial virus, tick bornejapanese encephalitis, pneumococcus, streptococcus, typhoid, influenza,hepatitis, including hepatitis A, B, C and E, otitis media, rabies,polio, HIV, parainfluenza, rotavirus, Epstein Barr Virus, CMV,chlamydia, non-typeable haemophilus, moraxella catarrhalis, humanpapilloma virus, tuberculosis including BCG, gonorrhoea, asthma,atheroschlerosis malaria, E-coli, Alzheimers, H. Pylori, salmonella,diabetes, cancer, herpes simplex, human papilloma and the like othersubstances including all of the major therapeutics such as agents forthe common cold, Anti-addiction, anti-allergy, anti-emetics,anti-obesity, antiosteoporeteic, anti-infectives, analgesics,anesthetics, anorexics, antiarthritics, antiasthmatic agents,anticonvulsants, anti-depressants, antidiabetic agents, antihistamines,anti-inflammatory agents, antimigraine preparations, antimotion sicknesspreparations, antinauseants, antineoplastics, antiparkinsonism drugs,antipruritics, antipsychotics, antipyretics, anticholinergics,benzodiazepine antagonists, vasodilators, including general, coronary,peripheral and cerebral, bone stimulating agents, central nervous systemstimulants, hormones, hypnotics, immunosuppressives, muscle relaxants,parasympatholytics, parasympathomimetrics, prostaglandins, proteins,peptides, polypeptides and other macromolecules, psychostimulants,sedatives, sexual hypofunction and tranquilizers and major diagnosticssuch as tuberculin and other hypersensitivity agents.

FIG. 1 shows a delivery device having aspects of the invention. Deliverydevice 10 includes a syringe 11 with a barrel 40 and plunger 30. Plunger30 is inserted into barrel 40 at the proximal end of device 10. At thedistal end of plunger 30 is a stopper which is used to seal barrel 40 toform a reservoir for the drug substance. At the proximal end of plunger30 is push pad 32. At the distal end of barrel 40 is attached needleassembly 12. Needle assembly 12 is preferably comprised of hub 50 havinga needle, sheath 80 and shield 70. Shield 70 is removably attached tothe distal end of needle assembly 12. Preferably, needle assembly 12 isattached to barrel 40 via a threaded luer connection, however otherconnection methods may be used, inter alia luer slip or integralformation. Optional sheath 80 is slidably connected to hub 50 in orderto protect the needle after use of the device. Alternatively, aconventional needle assembly may be used such as the type depicted inU.S. Pat. No. 6,494,865 to Alchas, the entire contents of which isincorporated by reference herein, or a standard hypodermic detachableneedle. Alternatively, the needle may be integrally assembled onto orinto the barrel 40, such that it is a not removable barrel. Typicallybarrel 40 is plastic but it may be comprised of glass or any othermaterial suitable for drug delivery. At the proximal end of deliverydevice 10 is dose divider 13. Preferably, dose divider 13 includes aslider 20 and clip 60 which cooperate with plunger 30 to divide theentire dose contained within the syringe 11 into preselected increments.The construction and operation of the dose divider 13 is more readilyseen in FIG. 2 and is described below.

Now turning to FIG. 2, the dose divider 13 includes a slider 20 having abutton 21 which is depressible by the health care professional. Slider20 includes follower 28 which cooperates with track 100 of plunger 30 todivide the entire dose of the drug substance contained in the reservoirof the syringe into discrete unit doses. The unassembled slider is shownin FIG. 4. Slider 20 includes follower 28 which is preferably mounted ondeflectable beam 27. In this embodiment opening 26 serves to allow beam27, and thus follower 28 to deflect in the radial direction. Thus sinceopening 26 is a closed hole, beam 27 is a double supported beam.Alternatively, opening 26 could be formed such that beam 27 is acantilevered beam. Alternatively, opening 26 could be omitted such thatfollower 28 is located on a rigid portion of slider 20, and follower 28and/or track 100 is elastically deformed and movement on a beam is notrequired. In this case, the parts would be sized dimensionally such thatthe interference of the parts was not so great to cause permanentdeformation of the parts. Preferably, slider 20 also includes at leastone rail 22 which cooperates with features on clip 60 to allow secureslidable engagement between the parts. Follower 28 is a cylindricalprotrusion with a portion which is chamfered. Other profiles ofprotrusions may be used for follower 28. Slider 20 is slidably engagedto clip 60 which is attached to barrel 40. The engagement of slider 20and clip 60 is shown clearly in FIG. 6. Rails 22 cooperate with opening62 on the proximal side of clip 60 to provide a secure slidingconnection between clip 60 and slider 20. Other slidable connectionmeans may be employed inter alia detents, holes and pins, and slots andfollowers. Clip 60 optionally includes radial opening 68 which receivesa flanged portion of barrel 40. Slider 20 with clip 60 attached tobarrel 40 and slider 20 slidably engaged to clip 60, slider 20 is ableto be slid in a radial direction with respect to the longitudinal axisof barrel 40, which would extend through barrel opening 69 on distalside of clip 60. Furthermore, substantial proximal and or distalmovement of follower 28 with respect to barrel 40 is substantiallyprevented by the design of slider 20, clip 60 and connection methodsemployed. Preferably, crush ribs 67 of clip 60 are used to provide asecure connection between flange of barrel 40 and clip 60, whichsubstantially prevents relative movement in the barrel axial direction.Optionally, all of the aspects of Clip 60 described herein would bereadily integrally formed into barrel 40, however, for ease of usingglass barrels, clip 60 is a separate component, however since theconnection of clip 60 to barrel 40 is a connection which prevents anysubstantial distal or proximal movement of clip 60 to barrel 40, they(clip 60, barrel 40) function as one. Clip 60 optionally includestactile ribs 61 for gripping by the health care professional. Clip 60 isattached to the distal end of barrel 40, which preferably includes aflange. In this embodiment, Clip 60 is slid radially onto a flange ofbarrel 40 before insertion of plunger 30 into barrel 40. Clip 60 alsopreferably includes tang 66 which serves to guide plunger 30 in use ofdose divider 30. Now referring back to FIG. 2, for clarity, slider 20 isonly shown with follower 28 outside of track 100 of plunger 30.Furthermore, this setting of slider 20 enables use of the syringe 11 asif there were no dose divider 13 attached. In this setting, follower 28does not interact with track 100 to substantially hinder distal orproximal movement of plunger 30. The dose dividing operation andcooperation of follower 28 and track 100 are further shown in FIGS. 5,8, and 9A-9B.

Shown in FIG. 5 is the plunger 30. Plunger 30 comprises distal end withstopper retention means 33, and proximal end with push button 32. Alongan exterior surface of plunger 30 is track 100. Track 100 is comprisedof one or more discrete units 101 which each of which correspond to aunit dose. The distance between units on Plunger 30 is directlycorrelated to the amount of substance delivered for each unit. In oneembodiment units are of equal size, thus providing equal volumetric unitdoses. In an alternate embodiment, the units are differing sizes, thusproviding varying volumetric unit doses. Optionally, track 100 includeson distal portion of plunger 30 a starting portion 107. Optionally,track 100 includes on proximal portion of plunger 30 an ending portion108. These portions are described more fully below and in FIG. 9A-B. InFIG. 9B one can see a detail of starting portion 107 of track 100. Thetwo positions of the follower 28 are represented in FIG. 9B by theposition circles labeled A and B, labeled reference numerals 128 and129, respectively. Position A 128 represents a position of the followerthat is outside of track 100. In this position there is no interferenceof the movement of the plunger 30 by the follower 28. To activate thedose dividing system the follower 28 is biased in the direct of thearrow labeled 118, from position A 128 to position B 129. In position B129 the follower is within the track, and subject to the guidance oftrack 100. More specifically the follower 28 is within the startingportion 107 of the track 100; however, it is not mandatory that thefollower 28 start in the starting portion 107 of the track 100, onlythat in order to use the device the follower 28 is within the track 100.In FIG. 9A one can see a detail of finishing portion 108 of track 100with angled wall 112. Furthermore, the details of the unit 101 aredescribed below and in FIG. 8.

Now turning to FIG. 8, the sides of plunger 30 comprise track 100 with aplurality of spaced units 101. Preferably units 101 are “Z” shaped.Track 100 has angled portions 102 with angled wall portions 112, whichare skewed from the longitudinal axis of plunger 30. Track 100 alsocomprises a plurality of abutting walls 110 which are a portion of track100 which is substantially perpendicular to the longitudinal axis ofplunger 30. Track 100 also preferably comprises a plurality of detenttabs 104 which are aligned substantially parallel to the longitudinalaxis of plunger 30. In the first position the slider 20 is positionedsuch that the follower 28 of the slider 20 does not interact with thetrack 100 of plunger 30. A filling needle is attached to the syringebarrel. The first position of slider as described above is the fillingposition and allows syringe 11 to be used as a conventional syringe;however, in usage of delivery device 10 in the first position of slider20 primarily serves to fill the syringe using either a filling needle orneedle assembly 12 without any substantial interference. Thus theplunger 30 may enter the barrel 40 along the length of the plunger 30with no stoppages. If a filling needle is employed, the filling needleis removed from the barrel and needle assembly 12 is attached inpreparation for the unit dosing, after the entire dose is drawn into thebarrel 40. In preparation for unit dosing, the slider 20 is moved to asecond position in the direction of arrow 114, upon which the follower28 is now within track 100.

Preferably, the follower 28 is positioned within the track at thestarting position 107 (shown in FIG. 9B) which serves as an area topurge the syringe of air and set the plunger to the first unit dose,however, the follower may be placed directly in one of the plurality ofunits. The health care professional then moves the plunger 30 distally,in the direction of arrow 115. The follower 28 is then directed toposition “P0” at the proximal end of starting position 107 via theangled wall 112 of track 100. The dose expelled during this phase isoptionally discarded. Alternatively, the dose created during this phaseis injected into the patient. When the follower reaches position “P0”labeled as reference numeral 119, the follower 28 abuts abutting wall110 and distal movement of the plunger is prevented. Position “P0” isthe initial position of unit dosing which corresponds to positionlabeled “P1” identified by reference numeral 120 in FIG. 8. As distalmovement of the plunger is prevented by abutting wall 110, the healthcare professional depresses the slider button 21 to move slider 20radially in the direction of arrow 114, and reset the dose divider 13.Preferably, follower 28 abuts detent tab 104 which provides resistanceto follower 28, thus the slider 20 to move in the radial direction;however, since follower 28 is flexibly mounted on beam 27 of slider 20,movement in the radial direction is possible with deflection of thefollower. As discussed previously, a designed deformation of thefollower, track or combinations thereof would serve the same purposes.The resistance of the deflection of follower 28 over detent tab 104 ispreferably selected so that it gives tactile feedback to the health careprofessional that the next dose is ready to be delivered. Optionally,the follower 28, beam 27 and detent tab 104 dimensions are selected suchthat an audible click is heard by the health care professional.

As the follower 28 has now passed detent tab 104, the follower is now atposition labeled “P2” identified by reference numeral 121 at the distalend of unit 101. Thus, this is the start of the unit 101 and the startof the delivery of a unit dose. The health care professional inserts theneedle 56 into the patient and depresses the plunger 30, preferably bypush button 32. As the push button 32 is depressed and the plunger 30begins to move distally, and since the follower 28 is contained withintrack 100, the follower 28 travels along the angled portion 102 of track100. Angled wall 112 biases follower 28 in the direction of arrow 116,and therefore moves slider 120 in the direction of arrow 116. Angledwall 112 serves to cam the follower into another position. At theapproximate middle of the unit 101, the follower is now at positionlabeled “P3” identified by reference numeral 122, in which as thefollower 120 travels along the angled portion 102 of track 100, theslider 20 is radially moved proportionally to the distal movement of theplunger 30, dependant on the angle of angled portion 102. As thefollower 28 reaches position labeled “P1′” identified by referencenumeral 120′ at the proximal end of unit 101, the follower 28 reaches astop point which is the beginning of the adjacent unit 101, wherein theplunger 30 is prevented from moving distally by the interaction offollower 28 and abutting wall 110. Thus, the resetting of the dosedivider process is repeated to bring the follower to position labeled“P2′” which is labeled with reference numeral 121′. The practitionerthen moves the needle to a new injection site and repeats the process ofinjection. This process continues until the entire dose is delivered ina series of unit doses. Optionally, the last unit dose has the follower28 traveling within the ending portion 108 (shown in FIG. 9A) of track100. In the ending portion 108 there is a large space of track 100 whichallows follower 28 of slider 28 to move radially, which indicates to thehealth care professional that the last dose is delivered. The volumetricunit doses are comprised of the axial distance between positions P2 andP2′ multiplied by the area of the cross section of the barrel 40.Preferably, the unit doses are equally spaced, although it would bepossible to pre-select unit doses of varying volumes by selecting thespacing of P2 and P2″ for each unit 101 of track 100.

Now turning to FIGS. 11A-B and FIG. 12 which shows an alternateembodiment of dose divider which is similar to the dose divider asdescribed above. The dose divider of this embodiment contains similarfeatures and operates similarly to the dose divider as described abovewith a modification in the track and configuration of the unit and theaddition of a biasing feature between the slider and the clip. Plunger30 of this embodiment comprises track 200 having unit 201. Furthermoreclip 600 has slider 220 integrally formed therein. Clip 600 is slideonto flange 41 of barrel 40 as described above. Clip 600 also comprisesstabilizer 255 which serves to stabilize plunger 30 and slider 220, aswell as secure the clip 600 onto the flange 41, or combinations of thesepurposes. Slider 220 further comprises follower 280. In this embodimentfollower 280 is a ratchet-like protrusion on slider 220, although mayhave other shapes, such as any of the embodiments described herein.Slider 220 is biased radially outward by biasing means 250. In thisembodiment biasing means 250 are a series of integrally molded leafsprings 251. Biasing means 250 is designed to place a bias to slider 220and therefore follower 280 in the operation of the device. Slider 220also contains optional push button 210. Although Slider 220 isintegrally formed with clip 600, slider 220 is able to be slid in aradial direction with respect to the longitudinal axis of barrel 40.Furthermore, substantial proximal and or distal movement of follower 280with respect to barrel 40 is substantially prevented by the design ofslider 220, clip 600 and connection methods employed. Optionally, all ofthe aspects of Clip 600 described herein would be readily integrallyformed into barrel 40, however, for ease of using glass barrels, clip600 is a separate component, however since the connection of clip 600 tobarrel 40 is a connection which prevents any substantial distal orproximal movement of clip 60 to barrel 40, they (clip 60, barrel 40)function as one.

Now turning to FIG. 12, as the follower 280 has three positions (P1, P2,P3) which will be described below. At the beginning of a unit dose,follower is located as position “P1.” In order to begin the dosingsequence, the health care professional depresses button 210 whichapplies a bias to slider 220 in the direction of arrow 114 and thusforces follower 280 to pass now passed detent tab 104, the follower 280is now at position labeled “P2” identified by reference numeral 121 atthe distal end of unit 201. The health care professional inserts theneedle 56 into the patient and depresses the plunger 30, preferably bypush button 32. As the push button 32 is depressed and the plunger 30begins to move distally in the direction of arrow 115, and since thefollower 280 is contained within track 200, the follower 28 travelsalong track 200. However, since there is a bias applied by bias means250 applied to the slider 220 and follower 280 in the direction in thedirection of arrow 202, and therefore moves slider 220 in the directionof arrow 202. At the approximate middle of the unit 201, the follower isnow at position labeled “P3” identified by reference numeral 122, inwhich as the follower 280 travels along track 200, the slider 220 isbiased by bias means 250 into the capture portion 202 of track 200. Asthe follower 280 reaches position labeled “P1′” identified by referencenumeral 120′ at the proximal end of unit 201, the follower 280 reaches astop point which is the beginning of the adjacent unit 201, wherein theplunger 30 is prevented from moving distally by the interaction offollower 28 and abutting wall 110. Thus, the resetting of the dosedivider process is repeated to bring the follower to position in whichthe plunger may be moved distally as described above. The practitionerthen moves the needle to a new injection site and repeats the process ofinjection. This process continues until the entire dose is delivered ina series of unit doses. Optionally, the last unit dose has the follower280 traveling within the ending portion of track 200, similarly asdescribed in the previous embodiment. As in the previous embodiment, thevolumetric unit doses are comprised of the axial distance betweenpositions P2 and P2′ multiplied by the area of the cross section of thebarrel 40. Preferably, the unit doses are equally spaced, although itwould be possible to pre-select unit doses of varying volumes byselecting the spacing of P2 and P2″ for each unit 201 of track 200.

Now turning to FIG. 7A which shows an alternate embodiment of dosedivider 1300 which uses a radially moving collar 160 having acantilevered beam 270 which serves as a pawl having follower 280. Thecollar 160 is slidable from a first position to a second position on theflange of the barrel 40. Furthermore, the plunger 30 of the device isratcheted with a plurality of spaced detents 1110. Detents 1110 areformed into units 1010. In the first position collar 160 is positionedsuch that the follower 280 of the cantilevered beams 270 do not interactwith the detents 1110 of the plunger 30. A filling needle is attached tothe syringe barrel. The first position is the filling position andallows the syringe 11 to be used as a conventional syringe; however, inthe usage of this device, the first position of collar 160 primarilyserves to fill the syringe using a filling needle without interferenceby the dosing device 1300. The filling needle is removed from the barreland a needle assembly 12. The collar 160 is moved to a second positionon the flange of barrel 40. In the second position the collar 160 ispositioned such that the follower 280 of the cantilevered beams 270interfere with the detents 1110 of the plunger 30. This is the discreteinjection position and allows the syringe 11 to be used as a multiplerepeat dose device. The practitioner inserts the needle into the patientand depresses the plunger. As the plunger is depressed, the follower 280interacts with the detents 1110 which provide for tactile feedback tothe health care professional that the discrete intermediate dosage hasbeen delivered. The health care professional then moves the needle to anew injection site and repeats the process. This process continues untilthe entire dose is delivered.

Now turning to FIG. 3 and FIG. 10, the needle assembly 12 includes aneedle cannula 56 located at the distal end of the hub 50. In theembodiment depicted in FIGS. 3 and 10, needle 56 is inserted into hub 50defined at that distal end of needle assembly 12 in a manner known tothose skilled in the art. For example, needle 56 may be secured using afriction fit, snap fit, suitable adhesive, solvent weld, or other nowknown or hereafter developed means of securing a needle to a hub. Sheath80 is slidably engaged to hub 50 by ribs 53, 54. In one embodiment rib54 has detents which cooperate with detenting means 82 to lock sheath 80in at least one of two or more positions. In the intradermal embodimentof needle assembly 12, hub 50 includes a specifically designed skinengaging surface 57, which cooperates with needle 56, extending from thedistal end of surface 57 from 0.3 mm to 3 mm, preferably 0.5 mm to 1.5mm.

FIG. 10 shows a cross section of needle assembly 12 attached to distalend of barrel 40. Barrel 40 comprises collar 48 which contains internalthreads 49 which engage with external threads 58 of hub 50. Barrel 40also comprises luer tip 46 which has a taper of “L” degrees. Typically“L” is approximately between 1.5 and 2.0 degrees. Preferably “L” isapproximately 1.75 degrees. Hub 50 also has a corresponding taper withinluer opening 51. Preferably, luer opening 51 of hub 50 is adapted toonly receive specialized luer tip 46 of barrel 40. Luer opening 51 isdesigned to have a stepped opening, such that standard luer tips ofstandard syringes will not fully engage luer opening 51 and thus beun-usable with hub 50 of needle assembly 12. Luer opening 51 iselongated and has a depth dimension of D1+D2. Preferably, dimension D2is selected such that it is greater than the extension of standard luertips. More preferably, dimension D2 is selected such that it does notallow engagement of threads 58 into standard luer lock barrels, but thefact that hub proximal end 51 protrudes at distance D2 from threads 58,this does not allow engagement of the components. The interior diameterbetween D1 and D2 has a discontinuity 59 of dimension D3 such that astep is formed at the interface between D1 and D2. Typically D3 rangesfrom 0.05 mm to 0.15 mm, preferably approximately 0.1 mm. Typically D1ranges from 6 mm to 10 mm, preferably approximately 8 mm. Typically D2ranges from 4.5 mm to 8.5 mm, preferably approximately 6.5 mm. Thelocation of the discontinuity 59 is selected such that effective use ofhub 50 on standard luer tips is prevented. Preferably, the location ofdiscontinuity 59 is at the same location as threads 58 along hub 50.However, since the distal end of luer tip 46 is standard in nature, luertip 46 allows attachment of a standard luer needle with no degradationin performance. As such, luer tip 46 allows both use of a standard luerneedle for filling and hub 50 of specialized needle assembly 12 forinjection.

Preferably inserted in the internal diameter of luer tip 46 isrestrictor pin 92. Restrictor pin 92 is substantially cylindrical andcomprises a flattened portion 93 such that when restrictor pin 92 isinserted into internal diameter of luer tip 46, the internal diameter issubstantially but not completely obstructed to form flow path 91.Preferably flow path 91 is sized to enable effective filling of deliverydevice 10 and prevent excessive shear forces on any substancesdelivered. Restrictor pin 92 also optionally comprises detent 94 whichcooperates with optional detent rib 44 within luer tip 46 which servesto retain restrictor pin 92 in luer tip 46. Other methods may be used toretain restrictor pin 92 in luer tip 46. Hub 50 has dead space 90 whichis included of the overall dead space of the system. It may be desirableto add a second restrictor pin within hub dead space 90, as well.Alternatively, an elongated restrictor pin of similar design may be usedin both spaces. Thus, restrictor pin 46 serves to reduce the overall“dead space” of delivery device 10.

In use, a health care professional administering the injection willunwrap the protective packaging from the vial. The health careprofessional will then manually insert the medication device into thevial in preparation for aspiration of medication into barrel 40. Ifsupplied as separate components, the health care professional will thenmanually insert the syringe 11 into the filling needle in preparationfor aspiration of medication. Alternatively, the filling needle anddelivery device 10 are pre-assembled in a kit supplied with needleassembly 12. In another embodiment, all three components (needleassembly 12, syringe 40 and the filling needle are supplied in a kit. Inanother embodiment, syringe 40 is pre-filled with the drug substance andno filling is required. In another embodiment, syringe 40 is pre-filledwith a diluent. Optionally, at this point, a diluent is injected in themedication vial. The healthcare professional then aspirates the syringewith the medication from the medication vial from syringe 11. The healthcare professional will then manually remove the syringe 11 from thefilling needle in preparation for administration of the injection. Theneedle assembly 12 is then attached to the device. In anotherembodiment, the filling needle is the same needle as the needle assembly12. Administration will, in one embodiment, involve pressing the skinengaging surface 57 of the hub 50 substantially perpendicular to asurface of the patient's skin. The first unit dose of the drug substancewill then be injected using the plunger 30. As the plunger is depressedthe follower of the dose divider 13 follows the path of the track100,200. The follower then reaches stop point 122. Upon completion ofthe unit dose, the health care professional withdraws the needle cannulafrom the patient's skin and prepares to reset the dose divider.Optionally the health care professional prepares the next injectionsite. The dose divider 13 is then reset in order to deliver the nextunit dose, which entails moving the follower to start point 120.Preferably, the reset involves pushing a button on the slider such thatthe follower is moved into the start point 120. This cycle is thenrepeated for the number of units along the length of the plunger. Uponcompletion of the entire dose, the health care professional withdrawsthe needle cannula from the patient's skin and disposes the usedinjection device 10 in a suitable container. Prior to disposal, thehealth care professional optionally activates the shielding portion ofdelivery device by sliding sheath 80 distally.

As will now be understood, the delivery device having aspects of theinvention may include a needle enclosure means which encloses orconceals the needle cannula tip following injection and which preferablycannot be retracted to prevent accidental needle contact or reuse. Inthe embodiment shown in FIGS. 1 and 3, a sheath 80 may be extendedfollowing injection and locked in place. The assembly includes sheath 80which locks in the extended position, preventing contact with the needleby use of locking means 82. Optionally arm 84 extends for the mainpotion of sheath 80 to aid in activation.

The invention has been described in an illustrative manner, and it is tobe understood that the terminology which has been used is intended to bein the nature of words of description rather than of limitation.

Obviously, many modifications and variations of the present inventionare possible in light of the above teachings. It is, therefore, to beunderstood that within the scope of the appended claims, whereinreference numerals are merely for convenience and are not to be in anyway limiting, the invention may be practiced otherwise than asspecifically described.

What is claimed is:
 1. A multiple dose injection device comprising: afluid conduit; a barrel having a bore, a distal end, and a proximal endwherein the fluid conduit is located at the distal end of the barrel, influid communication with the bore and the proximal end of the barrel isadapted to receive a stopper; a plunger having a distal end and aproximal end and a longitudinal axis wherein the stopper is connected tothe distal end of the plunger and movable within the barrel, and theplunger has at least one continuous track formed between the distal andproximal ends of the plunger wherein the at least one continuous trackfurther comprises at least one of each of the following: a first restposition, a stop position, having a proximal abutment, a second restposition, a camming portion which is skewed to the longitudinal axis ofthe plunger and formed between the first rest position and the stopposition; a loading portion of the at least one continuous track locatedat a distal portion of the plunger; a reset portion substantiallyperpendicular to the axis of the plunger and formed between the stopposition and the second rest position; and, a slider having a followermovable substantially perpendicular to the axis of the plunger, theslider having a user-pressable portion; wherein when a portion of theplunger is depressed by a user, the follower moves with respect to theplunger along the camming portion of the at least one continuous track,thereby causing radial motion of the follower and movement of thefollower to the stop position at which position a plunger distalmovement is prevented by contact of the follower to the proximalabutment, wherein the user may apply a biasing force to theuser-pressable portion of the slider, thereby moving the follower alongthe reset portion to the second rest position and wherein the loadingportion constrains movement of the follower to the stop position.
 2. Thedevice as set forth in claim 1 wherein a pattern of the first restposition, stop position, and second rest position are repeated along theplunger at an axial distance between corresponding positions, whereinsaid axial distance multiplied by a cross sectional area of the bore isa unit volume which comprises a unit dose.
 3. The device as set forth inclaim 3 wherein the unit dose is a plurality of unit doses and all unitdoses are substantially equal.
 4. The device as set forth in claim 1further comprising a clip which engages a flange on the barrel and theslider is slidably engaged to the clip.
 5. The device as set forth inclaim 4 the clip further comprising a plunger guiding portion.
 6. Thedevice as set forth in claim 4 wherein the clip and slider areintegrally formed with a slidable relationship.
 7. The device as setforth in claim 1 wherein the follower is mounted on a deflectable beam.8. The device as set forth in claim 1 wherein the follower iselastically deformed in use.
 9. The device as set forth in claim 7wherein the reset portion further comprises a detent tab located in theat least one continuous track which deflects the follower.
 10. Thedevice as set forth in claim 7 wherein the reset portion furthercomprises a deflectable detent tab located in the at least onecontinuous track.
 11. The device as set forth in claim 9 wherein thedeflection creates an audible sound, thereby providing feedback to theuser.
 12. The device as set forth in claim 1 wherein the fluid conduitfurther comprises a detachable needle assembly having a hub, attachableto the distal end of the barrel and a needle inserted into the hub. 13.The device as set forth in claim 12 wherein the hub further comprises aproximal opening adapted to receive an elongated luer tip located at thedistal end of the barrel and is adapted to prevent effective use of astandard luer tipped barrel.
 14. The device as set forth in claim 1further comprising a hub engaged to the barrel having a needle coverremovably attached to said hub.
 15. The device as set forth in claim 14further comprising a shield which is slidably engaged to the hub.
 16. Amultiple dose injection device comprising: a fluid conduit; a barrelhaving a bore, a distal end, and a proximal end wherein the fluidconduit is located at the distal end of the barrel, in fluidcommunication with the bore and the proximal end of the barrel isadapted to receive a stopper; a plunger having a distal end and aproximal end and a longitudinal axis wherein the stopper is connected tothe distal end of the plunger and movable within the barrel, and theplunger has at least one continuous track formed between the distal andproximal ends of the plunger wherein the at least one continuous trackfurther comprises at least one of each of the following: a loadingportion of the at least one continuous track located at a distal portionof the plunger, a first rest position, a stop position, having aproximal abutment, a second rest position, a capturing portion formedbetween the first rest position and the stop position; a reset portionsubstantially perpendicular to the axis of the plunger and formedbetween the stop position and the second rest position; and, a sliderhaving a follower movable substantially perpendicular to the axis of theplunger, the slider having a user-pressable portion; wherein thefollower is biased toward the stop position, thereby radially biasingthe follower in the capturing portion to the stop position at whichposition a plunger distal movement is prevented by contact of thefollower to the proximal abutment, wherein a user may apply a reversebiasing force to the user-pressable portion of the slider, therebymoving the follower along the reset portion to the second rest positionand wherein the loading portion constrains movement of the follower tothe stop position.
 17. The device as set forth in claim 16 wherein thefollower is movable from an initial position wherein the follower islocated outside of the at least one continuous track and does notinterfere with the plunger movement, to a first position wherein thefollower is located within the at least one continuous track.
 18. Thedevice as set forth in claim 16 wherein a pattern of first restposition, stop position, second rest position are repeated along theplunger at an axial distance between corresponding positions, whereinwhen said axial distance is multiplied by a cross sectional area of thebore is a unit volume which comprises a unit dose.
 19. The device as setforth in claim 16 wherein the follower is mounted on a deflectable beam.20. The device as set forth in claim 19 wherein the deflection of saiddeflectable beam creates an audible sound, thereby providing feedback tothe user.